Despite considerable attention to the sexual health of young men who have sex with men (YMSM), new HIV and STD infections are rapidly increasing among this population. A critical aspect of sexual behavior among YMSM is the process of sexual socialization - the process by which individuals gain knowledge, attitudes, and norms about sexuality, sexual behavior, and sexual risk. Sexual scripts theory provides a framework to understand the sexual socialization process, specifically how individuals receive cultural scenarios from external sources (cultural scripts), interpret them (intrapsychic scripts), and enact them with sexual partners (interpersonal scripts). To understand this phenomenon and inform the development of, and improve existing, interventions for YMSM, the proposed study will conduct mixed-methods interviews with an ethnically diverse sample of 160 urban YMSM (33% Black, 33% Latino, 33% White; of whom 50% within each racial/ethnic group will be ages 16-20 and 50% will be ages 21-25). Aim 1. Examine the content of cultural scenarios that YMSM are exposed to, from different sources, about when/what age they should have sex, who are acceptable partners, the frequency and types of sexual (risk) behaviors that are appropriate, and the role of substance use in sexual interactions. Aim 2. Examine the processes by which YMSM interpret, resolve discrepancies between, and enact these cultural scenarios into sexual behaviors, including the process by which scripts are reappraised and enacted differently over time (e.g., due to maturation, new relationship contexts, exposure to new cultural scenarios). Aim 3. Examine how the content and sources of cultural scenarios to which YMSM are exposed and their interpretation, enactment, and reappraisal of these scripts over time, differ by selected participant characteristics; and how these differences in scripts serve to explain differences in sexual risk behaviors. Aim 4: Investigate the views of YMSM regarding the need for, desired content of, and method of delivery for sexual education and HIV prevention interventions for YMSM.